This invention relates to a cardiac assist device or a device for assisting the pumping of a heart, and more particularly, to a catheter having a pump for draining the coronary sinus of the heart. Specifically, the coronary sinus pump assists in the venous drainage of the heart that should occur during both the diastolic and systolic function of the heart.
The heart is divided into a left side and a right side. The left side of the heart performs the function of pumping oxygenated blood from the lungs to the rest of the body. The right side of the heart receives deoxygenated blood returning from the body and then sends this blood to the lungs to be supplied with oxygen. Each side of the heart has an upper chamber, referred to as an atrium, and a lower chamber, called a ventricle. The atrial chambers accumulate blood and supply blood to the ventricular chambers that then pump blood to the body. The ventricular chambers operate in a pumping fashion by expanding and drawing blood in from the atriums, then contracting and forcing blood out to the body. Inlet and outlet check valves within the chambers operate to insure that blood flows in the proper directions. The right atrium and the right ventricle are separated by a tricuspid valve. The right ventricle pumps blood out through a pulmonary valve into pulmonary arteries that then carry blood away from the heart to the lungs. The left atrium and the left ventricle are separated by a mitral valve. The left ventricle pumps blood out through an aortic valve into the aorta that then carries oxygen-rich blood from the heart to the body.
Deoxygenated blood returns from the body to the right atrium of the heart by means of the superior vena cava and the inferior vena cava. Diastole is the resting phase in the heart cycle. Systole is the active or pumping phase of the heart. During the heart's diastole or expansion, blood is drawn through the tricuspid valve into the right ventricle. During the heart's systole or contraction, blood is forced from the right ventricle into the pulmonary artery. Oxygenated blood returns from the lungs via pulmonary veins and enters into the left atrium. During the heart's systole, blood is forced out of the left ventricle, through the aortic valve, and into the aorta to be carried off to all parts of the body including the heart. If the heart does not properly rest or relax, this can subsequently hinder the systolic phase or the pumping phase of the heart. This improper heart relaxation will compromise the ability of the heart to pump blood to the rest of the body. If this occurs, then the heart will fail.
The blood supply that serves the heart muscle with oxygenated blood originates from two openings called coronary ostia in the aorta near the aortic valve. Blood flows from the coronary ostia through the coronary arteries and branches off into many tiny capillaries to provide oxygenated blood to all areas of the heart muscle. Most of the blood entering the coronary arteries drains through veins into the coronary sinus vein that in turn drains into the right atrium. However, there are times when the heart is not able to drain blood in the coronary sinus back into the right atrium. This may be due to congestive heart failure or muscle damage caused by a heart attack. During periods of time in which the heart is not capable of moving some or all of the blood from the coronary sinus to the right atrium, it would be desirable and advantageous to provide a device for assisting the flow of blood from the coronary sinus back to the right atrium.
Accordingly, it is desirable and advantageous to provide a device for draining the coronary sinus to enhance the operation of a heart. The present invention is designed to facilitate venous drainage of blood from the coronary sinus to the right atrium or the right ventricle of the heart. In particular, the present invention assists in coronary venous drainage by employing a pair of catheters, a control device having a pump and a sensor pair that provides signals to the control device for the control device to operate the pump. The present invention also accomplishes venous drainage.